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Class

GPIO

Name

digitalRead()
Examples
import processing.io.*;

// On the Raspberry Pi GPIO 4 is physical pin 7 on the header

void setup() {
  // INPUT_PULLUP enables the built-in pull-up resistor for this pin
  // left alone, the pin will read as HIGH
  // connected to ground (via e.g. a button or switch) it will read LOW
  GPIO.pinMode(4, GPIO.INPUT_PULLUP);
}

void draw() {
  if (GPIO.digitalRead(4) == GPIO.LOW) {
    // button is pressed
    fill(255);
  } else {
    // button is not pressed
    fill(204);
  }
  stroke(255);
  ellipse(width/2, height/2, width*0.75, height*0.75);
}
Description Returns the value of an input pin, which is either GPIO.HIGH (1) or GPIO.LOW (0)

You need to set the pin to input by calling pinMode() before calling this function.
Syntax
.digitalRead(pin)
Parameters
pin int: GPIO pin
Returnsint
Updated on January 1, 2021 03:38:10am EST

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